The telecommunications industry has a defined set of performance and cost requirements, and an exponentially increasing demand for bandwidth. Even in today's market downturn, telecom network traffic still doubles approximately every year. Applications such as video on demand, telemedicine, interactive games and teleconferencing will increase the demands on the network infrastructure dramatically, outpacing the traditional technology. As an example, industry estimates suggest that there are about 100 million video rental transactions per week in the USA. Downloading this volume of information from the Internet would require a capacity of 40 terabits per second! In 2001, the Internet was believed to have a total capacity of about 15 terabits per second. Thus, the migration of just this single industry onto the internet would completely overload the existing infrastructure.
Given the global migration of industry to internet based business, there is an increasing and near critical need to address the mounting problem of bandwidth need. Even with the current “fiber glut”, many US market links are nearing capacity. As such, there is an unavoidable need to continue increasing available bandwidth within each fiber to meet capacity needs. This is especially true as we begin to move fiber into the home, eliminating local networks as the bandwidth-bottleneck in the telecommunications system. Traditionally, fiber bandwidth has been extended by either increasing channel bit-rates or tightening channel spacing. Both of these methods have problems, however, that will ultimately limit the maximum available bandwidth.
In principle, the one “limitless” source of bandwidth is achieved by expanding the wavelength range over which data can be transmitted. There are, of course, current practical limits to the available wavelength range defined by the transmission and dispersion of today's optical fibers; however, even these can efficiently transmit from 1200 nm to 1700 nm. To date, however, the available wavelength range for telecommunications has been limited to a narrow spectral band around 1550 nm due to the narrow gain spectrum of erbium doped fiber amplifier (EDFA) (efficient gain from 1535 nm to 1570 nm). Expanding beyond this range requires the introduction of new cost-effective amplification platforms that have so far eluded the industry.
The present invention proposes to meet the needs set forth above by using nanocomposite optical amplifiers (NOAs), e.g., provided on integrated optical chips, for cost-effective broadband amplification across the entire clear-window of optical fiber. It is expected that such systems could provide a 15× increase in bandwidth over existing technology, while remaining compatible with all future advances in bit-rate and channel spacing.
This technology will allow for low-cost, highly integrated active optical circuits using high-volume manufacturing techniques such as inkjet printing or screen printing. The ability to precisely engineer the properties of NOAs will allow deployment of integrated systems that initially mimic the functionality of traditional devices, providing seamless integration into today's network infrastructure and nearly limitless expandability in the future when it is truly needed (i.e., in 5–10 years).